$7\mathrm{.}14$ The solid rubber sole is very resistant to being compressed, because it is restrained against lateral Poisson's ratio expansion by being glued to the relatively stiff sole. However, the molded surface has a much lower resistance to being compressed, because the lateral Poisson's ratio expansion of each separate rubber cube can occur without constraint $($provided the gaps between adjacent cubes do not close up completely$).$ So your colleague is correct.